Reinforced concrete.



PATENTED FEB. 6, 1906.

E. B. JARVIS. REINFORCED CONCRETE. APPLICATION FILED 14u31. 1904.

' QNQ EDGAR BEAUMONT JARVIS, OFF TORONTQCANADA.

FIEINFFIGED` CONCRETE.

Specification of Letters Patent.

Patented Feb. 6, 1906.

Application ld May 31| 1904. Serial N0. 210,563.

scientifically-constructed truss to be incor o-y rated in concrete beams, columns, .or ot er supports, whereby the least amount of metal ronsistent with strength' will be employed in.

the construction; and it consists, essentially, of a lurality of bars of increasing length located) adjacently, having their ends bent obliquel'y, so that the bent portions incline toward the end of the beam or column; holes being rovided in the extreme ends of the bars, t ough which a central rod passes, unitin them.

igure 1 is a; pers ective view of a beam supported on a co umn partially broken away and insection 'toexhi it the construction of my truss. Fi 2 is an enlarged detail showing one truss an the central rod. Fig. 3

is a section throu h a b in the truss before the concrete is place about it. t

In the drawings like letters of reference 1ndicate corresponding parts in each figure.

A is the concrete beam, and B is one ofthe concrete columns on which itv rests.

lare located symmetrical C', C2, and C3 are bars of similar form, but of increasing length and located one above the other, as indicated in the drawings. e and f are holes rovided in the ends ofthe rods, through whic a central rod D passes.

The various bars constituting one truss are bound together at suitable oints, as g, by wire clam sor other .suitab e contrivances Inthe-co umn a pluralit7 of similar trusses y about a central rod, as shown, preferably with a truss opposite eachcorner.

D is a straight rod provided with a hole h in the end, which slips over the central rod of the supporting-column, insurinrigidity and forming a binding-tie. If the earn 1s continuous, a similar rod. D runs along the bottom "of the second-space, slip ing in place on the rod of the supporting-co unm above D. rIhe obli ue portions of the rods form the ties taking t e tensile stress,l the compressive stress being resisted by the cement, which 1s particularly strong in compression. The

mum depth of bars, such ldepth ecreasing as the bars approach `the end ofthe beam practicallyinpro ortion asthe bending moment f decreases.

nythe column it willy readily be seen that the metal isplaced in the most suitable place to prevent collapsing when the load is a plied..

It wilFreadily be seen from the form of trussthat I have designed that a maximum stress is obtained in the concrete beam with a minimum weight of metal.

In Fig. 3 I show' a Wire o r other bsuitable mesh E, which is stretched yaround the 'truss and forms a base for a coating of cement. After the cement is set it will be readily seen that a mold-box is formed into Whichthe cement is poured, so as to make a solid mass or column. By this means the expense of put ting up wooden forms is saved, which is an 1m ortant desideratum.

at I claim as my invention 1s'- 1. lIn cement columns in combination a plurality of trusses each consisting' of a central rod and a plurality of bars of different lengths and located one above the other, having their ends bent obliquely and convergin to the central rod said rod assing throng the ends of all the bars as am? for the purpose specied.

2. In cement structures, in combination a beam having in it a truss consistin of a cen-4 tral rod an lengths, located one above the other having a plurality of bars o different their ends bent obliquely, a column containing a plurality of like trusses secured to the centra rodand a link-bar connectingthe trussesin the beamand column as and for the purpose specified.

3. A strengthening truss or device for concrete structures comprising a frame composed of a plurality of sets of radially-arranged bars, each set consisting of a plurality of straight portions of different length se- IOO cured together and having inwardly-inclined portions connected to the inwardly-inclined portions of the other sets, and a Wire mesh encircling the setsof bars and in contact with the outer surface of the straight portions thereof, substantiall as described.

EDGAR B AUMONT JARVIS. Witnesses:

M. MCLAREN, J. P. HOLMES. 

